Install AT&T Galaxy S3 Android 4.2.2 Jellybro Custom ROM – SGH-I747

AT&T Samsung Galaxy S3 user now can upgrade to Android 4.2.2 Jelly bean latest firmware. This method we use an after market ROM. It’s called JellyBro. This is a AOSP based ROM, which mean it just like the Google Nexus device’s firmware. JellyBro based on the CyanogenMod 10.1, but it has unique customizations and some optimization tweaks.

This is not like the earlier introduced HellFire ROM, this one has some UI changes with unique features. AT&T Galaxy S3 jellybro installation we have to use Google apps zip file, because of this ROM doesn’t include Google’s apps. Moreover it doesn’t have AT&T and Samsung pre-installed apps and services. This firmware developed by the XDA developer Euroskank.

In order to install JellyBro custom ROM, you have to install a custom recovery and root your Galaxy S3. You can follow this tutorial requirement guides for that. Like other new firmware installation this method also wipes all the user data. Therefore it’s better to make a backup. Moreover this tutorial, I’ll guide you to install nAndroid backup. After installing Android 4.2.2 jellybro on AT&T Galaxy S3, if you need to go back to the older ROM you can use that saved files.

Warning!

Installing custom firmware voids the warranty. If your AT&T Galaxy S3 bricked by following this tutorial, I can’t claim its damages. Applying this tutorial at your own risk.

Power off the phone and boot into the recovery mode by pressing and holding SGS3 “Power, Home and Volume Up” keys at the same time for a few seconds.

When you see the recovery, release the pressed keys. Sometime you may have CWM or TWRP recovery. It’s not an issue.

First it’s better to make a complete ROM backup using nAndroid. Navigate to “backup and restore>backup. Now your existing ROM its data will be saved on the SD card. Anytime you can restore that saved files.